12.01.2013 Views

Source Code Analysis Laboratory (SCALe) for Energy ... - CERT

Source Code Analysis Laboratory (SCALe) for Energy ... - CERT

Source Code Analysis Laboratory (SCALe) for Energy ... - CERT

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Table 9: <strong>Analysis</strong> Results, <strong>Energy</strong> Delivery System B<br />

False Suspicious True Unknown Total<br />

ARR30-C 18 18<br />

ARR36-C 2 106 108<br />

DCL35-C 47 47<br />

DCL36-C 2 2<br />

EXP30-C 2 2<br />

EXP33-C 5 329 334<br />

EXP34-C 13 3 605 621<br />

EXP37-C 40 40<br />

EXP40-C 20 20<br />

FIO30-C 3 2 3 8<br />

FLP35-C 9 9<br />

INT31-C 603 2 6,971 7,576<br />

INT32-C 9 9<br />

MEM30-C 3 3<br />

MEM31-C 21 21<br />

MEM33-C 4 4<br />

MEM34-C 1 1<br />

MSC34-C 326 36 362<br />

PRE30-C 4 4<br />

PRE31-C 11 11<br />

STR30-C 11 11<br />

STR31-C 1 50 51<br />

STR32-C 11 11<br />

STR33-C 1 1<br />

Based on our experience with analyzing energy delivery system A, we added a new category of<br />

“suspicious.” This category includes flagged noncon<strong>for</strong>mities that could not easily be proven to<br />

be either true or false positives. This was frequently the case <strong>for</strong> dereferencing null pointers, <strong>for</strong><br />

example, where the pointer dereferences were unguarded but it was difficult to prove that the<br />

pointer was never null without per<strong>for</strong>ming whole-program analysis. Suspicious violations are<br />

treated as false positives in that they will not result in a system failing con<strong>for</strong>mance testing and<br />

will not stop the analyst from analyzing other flagged noncon<strong>for</strong>mities reported against the same<br />

coding rule. These are reported as suspicious so that the developer can examine these flagged<br />

noncon<strong>for</strong>mities and take appropriate measures.<br />

Overall, energy delivery system B had considerably more flagged noncon<strong>for</strong>mities than energy<br />

delivery system A, a significant number of which have already been determined to be true positives.<br />

CMU/SEI-2010-TR-021 | 36

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!